Genetic variations in wood properties of third generation Acacia mangium Willd. progeny tests from Sumatra, Indonesia

Acacia mangium Willd. is a fast-growing tree commonly used in pulp and paper production. Despite extensive planting, there is a need for genetic improvement to enhance wood properties for better pulp output. This study assessed genetic variations in moisture content, pilodyn penetration, specific gravity, fiber length, cell wall thickness, lumen diameter, and cellulose content in a third-generation progeny test of A. mangium in South Sumatra, involving 52 families. Averages for 3-year-old A. mangium were as follows: pilodyn penetration at 11.22 mm, moisture content at 117.18%, specific gravity at 0.44, fiber length at 1.01 mm, and alpha cellulose at 68.03%. Phenotypic variation of wood properties ranged from 3.53% to 19.62%, while genotypic variation was between 1.83% and 9.91%. There was a strong genetic correlation between pilodyn penetration and wood properties (specific gravity, holocellulose, and alpha cellulose) with individual heritability of wood properties estimates (h2i) from 0.09 to 0.37. Significant family differences were found in pilodyn penetration, specific gravity, fiber length, holocellulose, and alpha cellulose, with genetic gains of wood properties between 1.78% and 9.72%.